Radio frequency identification (“RFID”) uses electromagnetic fields and radio frequency (“RF”) signals to wirelessly communicate between a RFID reader (e.g., a local interrogator) and RFID transponder (e.g., a tag). RFID systems can be used for a wide array of purposes, such as inventory management and tracking, access control, or wireless data communication.
A typical RFID transponder includes an integrated circuit (“IC”) for storing information and an antenna for sending and receiving signals from the RFID reader and is either active or passive. Active RFID systems include a power source such as a battery for powering the IC and antenna. However, in passive RFID systems, the RFID transponder does not include a power source; instead, the transponder harnesses energy from an interrogation signal sent by the RFID reader and received by the antenna and then utilizes that energy to identify itself or other information associated with the transponder.